1. Field of the Invention
The present invention relates generally to pilot burner apparatus, and more particularly, but not by way of limitation, to pilot burner apparatus of the type used to ignite combustible materials emitted from one or more other burners in flares, heaters and other similar apparatus.
2. Description of the Prior Art
A great variety of pilot burner designs and apparatus have been developed and used over the years. Generally, a pilot burner functions to provide a continuous pilot flame adjacent one or more main burners for igniting combustible materials periodically emitted from the main burners. Examples of applications of pilot burners in association with main burners are domestic and industrial heaters, boilers, dryers, etc. In addition, a variety of emergency and/or waste disposal flare apparatus for burning combustible materials are utilized in industry which include pilot burners.
In the above mentioned and other applications for pilot burners, it is desirable that the pilot burners have maximum flame stability in a variety of environmental conditions, i.e., that the burners be capable of maintaining a pilot flame in various forms and quantities of draft, at varying inlet combustible gas pressures, when exposed to draft or winds from various directions and other similar conditions. In addition, it is desirable that a pilot burner have the ability to maintain flame stability upon short duration combustion disturbances. The term "combustion disturbance" is used herein to mean any of a number of circumstances causing flame instability and a possible flame outage such as a combustible gas flow interruption, the flame being blown away from the pilot by wind, snuffed by wind or a momentary increase in external pressure, pulled away from the burner by momentary decreases in external pressure, etc.
By the present invention, pilot burner apparatus is provided having improved operational stability and other characteristics including the ability to maintain flame stability during and after short-term combustion disturbances.